Are you looking to automate the installs of just Java or anything that comes your way?
This is kind of a two part question:
1) How to automate installation
2) How to deploy the installation to 200+ computers
(since you obviously just don't want to push the .exe file to the computers and have the install sitting there waiting for someone to click "Next")
It depends on the software that you're trying to install. If it's an MSI package, first make a batch file that'll launch the MSI file with the /qb switches and the default install will be performed. If it's an Installshield-based install, first you have to run the .exe file from CMD with the -r command, then grab the setup.iss file from the Windows directory and drop it where the .exe file is. Then create a batch file that'll say something like this setup.exe /s /f1\\locationOfinstall\setup.iss. I've mostly automated MSI and Installshield so haven't worked with the others. After you have the automated install piece done, you have to deploy (obviously). If you don't have fancy software to push out to all the machines (Altiris, SMS, etc), then you're short on options, and have to figure out why group policy isn't working.
Mass deployment is very popular, so I wouldn't be surprised if you found detailed directions on how to mass deploy Java.
Let us know if you need more details.
Also, give us some details on how you're using group policy to deploy it, along with the MSI/ZAP that you're using